A known apparatus to provide beam steering of a phased array antenna is the so-called Butler matrix which is a matrix transmission network with a considerable number of transmission lines or cables where beam steering is accomplished by switching the signal paths between the input and output terminals of the network. Here, the electrical length of a required number of transmission lines is varied by means of electronic switches, such that the Butler matrix represents a passive structure with variable time delays. Since such a switched transmission line concept requires at least a half wave line length per antenna element, this type of structure requires at least this size in two dimensions, making it less suitable for miniaturization and monolithic integration in modern submicron IC technology. Furthermore, in order to limit RF losses, this type of passive structure requires a high quality RF (radio frequency) switch or varactor technology, which is not readily available in baseline integrated technologies.